We're working direct integrations with a variety of popular devices, but in the meantime you should be able to connect most newer devices using Google Fit, Apple Health, or a 3rd party fitness app as an intermediary.
3rd Party Devices and Android
Use the Health Sync app, or a similar third-party app, to link to Google Fit.
3rd Party Devices and iOS
First, check to see if your device is compatible with Apple Health. if so, use the Apple Health app. If that doesn't work (if your device isn't compatible), search for a third-party app.
Once you've connected your device to the appropriate health app, follow these steps to sync with Carb Manager.
You may need to refer to instructions for your specific fitness device to determine how to enable syncing on the device itself. Once your device is pushing calories burned (active energy), minutes exercised, and steps to Google Fit, Apple Health, or another compatible fitness app, Carb Manager will start importing the data.